Acid reflux can impact more than just the esophagus -- the tube that brings food from the throat to the stomach. Irritation of the esophagus and a burning sensation in the chest are common with acid reflux, but other organs can also be affected, especially when reflux has been present for a prolonged period of time. In some people, long-term acid reflux affects the lungs, structures in the throat and mouth, and even the nose and ears.
Acid reflux typically affects the esophagus, as the primary problem is the movement of acid from the stomach, where it is made, up into the esophagus. Chronic acid reflux can irritate and disrupt the lining of the esophagus, causing open sores, or ulcers, which can bleed and produce pain. As they heal, scar tissue may develop and the scarring may eventually lead to narrowing of the esophagus.
People with long-term acid reflux may develop a condition known as Barrett esophagus, in which the cells lining the lower esophagus transform to look like stomach cells. According to an article published in the March 2009 issue of “The Lancet,” about 5 to 15 percent of people who undergo investigations because of possible acid reflux are found to have Barrett esophagus. Individuals with this condition have a much higher risk of esophageal cancer than usual.
Throat and Voice Box
Acid reflux can sometimes climb all the way from the stomach to the upper esophagus and spill over into the throat and larynx, or voice box. The larynx and other parts of the throat are much more sensitive to acid than the stomach and esophagus. This may result in symptoms like hoarseness, a chronic cough, throat clearing, sore throat or postnasal drip. According to an article in the September 2012 issue of "Annals of Gastroenterology," chronic acid reflux accounts for about 20 percent of people with a chronic cough.
Mouth and Teeth
Acid that reaches the back of the throat can create a bitter or sour taste in the mouth, as well as bad breath. Acid reaching the teeth can also cause tooth decay. This is most likely to occur when acid reflux occurs over a long period of time during sleep, since lying in a horizontal position increases the chance that the acid will reach the mouth. In an upright position, gravity tends to keep the acid from traveling too far from the stomach. Dry mouth -- whether from acid reflux or medications used to treat it -- also contributes to the risk of tooth decay because the protective effect of saliva against bacteria is diminished.
Lungs and Airways
Acid reflux is a common trigger of asthma, and there is a kind of asthma called acid reflux-induced asthma. Differing theories account for the relationship between acid reflux and asthma, but there is no doubt that acid reflux can contribute to -- and worsen preexisting -- asthma. Long-term acid reflux is also associated with an increased likelihood of developing chronic bronchitis, emphysema and recurrent pneumonia.
Sinuses and Ears
Refluxed acid that reaches beyond the esophagus may sometimes lead to sinus problems. In some people who have long-term sinus inflammation despite usual sinus medications, acid reflux may be playing a role in causing their problems. Reflux may also interfere with the tube that connects the ear to the throat -- the eustachian tube. This can lead to frequent middle ear infections.